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I received two 7660, so no excuse to try again ...

The problem was that pin 2 & 4 of IC3, C21 + & - and C20 - were grounded.
I desoldered IC3 support, C21 and C22, and the problem was still there ... which means the problem came from the PCB.

So I resoldered an IC support but I removed pin 2 and 4. I soldered C21 directly to MAX1044, and C20 - directly to C21 +.

Now my sunking is working.

Hi,

IC1 = TL072              IC2 = TL072                 IC3 = MAX1044CPA
4.6                          4.6                             9.3   
4.6                          4.6                               0 (should be 4.6)
1.2 (should be 3.4)     4.6                               0
0                              0 (should be -8.5V)        0 (should be -4.5V)     
4.5                           4.6                              0 (should be -8.5V)
4.6                           4.6                             4.4
4.6                           4.6                             4.2 (a bit low)   
9.3                           8.2  (should be -16)       9.3       


Moreover IC3 is very very hot. All the electrolytic caps are 25 or 50V. I replaced them all but it changed nothing. I also replaced the zener.
I tried 3 different IC3 but all were MAX1044CPA. I read I should use MAX1044SCPA.
Do you know a place where to buy one with low shipping ?
What's the difference between CPA and SPCA ? Could this explain why my IC3 is so hot ? I can't let my finger on it !

I never took time to update this topic ! Never too late !

So I switched for a 100K log, and as expected the pot was more usable but there was still to much gain for me. I owned a Rat 2, and it was the same story.
So I tried some resistors in parallel, and finally I was happy with a 22K resistor. I checked the new value of my pot and it was 18K.
For the beginners, this is an easy mod which works with any pedal.

We could also remove some gain in increasing the 1K resistor before the clipping diode. I don't try this with this Rat clone because I'm happy with the gain set at 12h.

Check cap orientation, remelt solder on the pads for IC3 and C-19-C22, and then recheck the voltages and see if you get a different reading this time.

I did this and it changes nothing.
Once again, my build worked but I did a stupid thing = cut the excess of Z1 with the power on.

Hot IC3 and caps (C19-C22), what does it mean ?

My build worked but I noticed I have forgotten to add Z1. I added and tested it, it worked ... and I cutted the excess with the power on (yeah stupid) ...
The bypass always works but when I switch on, it's like a tremolo (the led works). grrrrr

IC3 and C19-C22 are really hot.

IC3
1- 9.3
2- 0
3- 0
4- 0
5- 0
6- 4.5
7- 4.2
8- 9.3

I tried another max1044 (IC3) and I got the same values.
The pin problems are 2, 4 and 5.
All electrolytic caps are 50V except C18 which is only 16V.

Thanks madbean I will try a log, but it will be a good thing to know if anyone noticed the same behaviour, because in my build the gain pot is unusefull (with the linear pot).

Thanks

Hi,

I noticed that the gain increased quickly when I turned the pot a little, and after it didn't change.
I used 100K linear.
Did anyone notice this problem ?

I added a swith for the Ruetz mod and it sounds good.

Thanks
Doc'.

I just built one and tried it quickly, and it works fine. I used TL072CN and MAX1044.
All the parts comes from smallbear.

maysink as jkokura said, a truebypass can be obtained using a relay. Depending on kind of relay, it will need to be power even in bypass mode.

I always socketed the diodes, and tred different ones. I loved 1N4148 (more volume and more highs). I will of course try to change the values of input caps.

I think that the G2 works better with Strat.

The darkside has two problems:
- Volume too low with Ge diodes
- Too Bassy

 

Hi,

It will be good to have the PCB size on each pdf project.

Thanks
Doc'.

Hi,

There is a verified schematic available on freestompboxes.
Can you do a PCB ?

Thanks
Doc Plus.